markers-test/test-mark-speed-local.c

   1 /* test-mark.c
   2  *
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/proc_fs.h>
   7 #include <linux/sched.h>
   8 #include <linux/timex.h>
   9 #include <linux/marker.h>
  10 #include <asm/ptrace.h>
  11 #include <asm/system.h>
  12
  13 static void pmc_flush_cache(void)
  14   {
  15     register int i;
  16     /* write back and invalidate cache (a serializing instruction) */
  17
  18     __asm__ __volatile__ ( "wbinvd" : : : "memory" );
  19
  20     /* The wbinvd instruction does not wait for the external caches
  21      * to be flushed, but only requests that it be done.  The loop
  22      * is to be sure that enough time has elapsed, but the compiler
  23      * might simplify or even remove it.  The loop bound is for a
  24      * 512 KB L2 cache.  On a Pentium Pro/II/III, the loop uses
  25      * 2 cycles per iteration.
  26      *
  27      * Does wbinvd also cause the TLB to be flushed?
  28      * A comment in mtrr.c suggests that it does.
  29      */
  30     for (i = 0; i < 512*1024; i++) {
  31       cpu_relax();
  32     }
  33   }
  34
  35
  36 static void noinline test2(const struct marker *mdata,
  37         void *call_private, ...)
  38 {
  39         unsigned char *ins = __builtin_return_address(0) - 5;
  40 #if 0
  41         /* not called */
  42         printk("ip %p\n", __builtin_return_address(0));
  43         printk("prev_ins %hX %hX %hX %hX %hX\n",
  44                 ins[0], ins[1], ins[2], ins[3], ins[4]);
  45 #endif //0
  46         ins[0] = 0x90;
  47         ins[1] = 0x8d;
  48         ins[2] = 0x74;
  49         ins[3] = 0x26;
  50         ins[4] = 0x00;
  51 }
  52
  53 /*
  54  * Generic marker flavor always available.
  55  * Note : the empty asm volatile with read constraint is used here instead of a
  56  * "used" attribute to fix a gcc 4.1.x bug.
  57  * Make sure the alignment of the structure in the __markers section will
  58  * not add unwanted padding between the beginning of the section and the
  59  * structure. Force alignment to the same alignment as the section start.
  60  */
  61 #define __my_trace_mark(generic, name, call_private, format, args...)   \
  62         do {                                                            \
  63                 static const char __mstrtab_##name[]                    \
  64                 __attribute__((section("__markers_strings")))           \
  65                 = #name "\0" format;                                    \
  66                 static struct marker __mark_##name                      \
  67                 __attribute__((section("__markers"), aligned(8))) =     \
  68                 { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)],   \
  69                 0, 0, marker_probe_cb,                                  \
  70                 { __mark_empty_function, NULL}, NULL };                 \
  71                 __mark_check_format(format, ## args);                   \
  72                 if (!generic) {                                         \
  73                         if (unlikely(imv_read(__mark_##name.state)))    \
  74                                 test2                   \
  75                                         (&__mark_##name, call_private,  \
  76                                         ## args);               \
  77                 } else {                                                \
  78                         if (unlikely(_imv_read(__mark_##name.state)))   \
  79                                 test2                   \
  80                                         (&__mark_##name, call_private,  \
  81                                         ## args);               \
  82                 }                                                       \
  83         } while (0)
  84
  85 struct proc_dir_entry *pentry = NULL;
  86
  87 static inline void test(unsigned long arg, unsigned long arg2)
  88 {
  89         volatile int temp[5];
  90 #ifdef CACHEFLUSH
  91         pmc_flush_cache();
  92 #endif
  93         temp[2] = (temp[0] + 60) << 10;
  94         temp[3] = (temp[2] + 60) << 10;
  95         temp[4] = (temp[3] + 60) << 10;
  96         temp[0] = (temp[4] + 60) << 10;
  97         //asm volatile ("");
  98         //__my_trace_mark(1, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
  99         barrier();
 100         test2(NULL, NULL, 2, 10, arg, arg2);
 101         barrier();      // make sure the compiler does not optimize marker conditions away!
 102         //__my_trace_mark(0, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
 103 }
 104
 105 static int my_open(struct inode *inode, struct file *file)
 106 {
 107         unsigned int i;
 108         cycles_t cycles1, cycles2;
 109         unsigned long flags;
 110
 111         local_irq_save(flags);
 112 #ifdef CACHEFLUSH
 113         pmc_flush_cache();      /* initial write back, without cycle count */
 114         msleep(20);     /* wait for L2 flush */
 115 #endif
 116         rdtsc_barrier();
 117         cycles1 = get_cycles();
 118         rdtsc_barrier();
 119         for(i=0; i<2000; i++) {
 120                 test(i, i);
 121                 test(i, i);
 122                 test(i, i);
 123                 test(i, i);
 124                 test(i, i);
 125                 test(i, i);
 126                 test(i, i);
 127                 test(i, i);
 128                 test(i, i);
 129                 test(i, i);
 130         }
 131         rdtsc_barrier();
 132         cycles2 = get_cycles();
 133         rdtsc_barrier();
 134         local_irq_restore(flags);
 135         printk("cycles : %llu\n", cycles2-cycles1);
 136         return -EPERM;
 137 }
 138
 139
 140 static struct file_operations my_operations = {
 141         .open = my_open,
 142 };
 143
 144 int init_module(void)
 145 {
 146         pentry = create_proc_entry("testmark", 0444, NULL);
 147         if (pentry)
 148                 pentry->proc_fops = &my_operations;
 149
 150         return 0;
 151 }
 152
 153 void cleanup_module(void)
 154 {
 155         remove_proc_entry("testmark", NULL);
 156 }
 157
 158 MODULE_LICENSE("GPL");
 159 MODULE_AUTHOR("Mathieu Desnoyers");
 160 MODULE_DESCRIPTION("Marker Test");
 161 MODULE_VERSION("1.0");
 162